introduce android_x64 build target

build/android.gypi

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 25 matching lines @@
       'android_ndk_root%': '<!(/bin/echo -n $ANDROID_NDK_ROOT)',
       'android_toolchain%': '<!(/bin/echo -n $ANDROID_TOOLCHAIN)',
     },
     'conditions': [
       ['android_ndk_root==""', {
         'variables': {
           'android_sysroot': '<(android_toolchain)/sysroot/',
           'android_stlport': '<(android_toolchain)/sources/cxx-stl/stlport/',
         },
         'android_include': '<(android_sysroot)/usr/include',
-        'android_lib': '<(android_sysroot)/usr/lib',
+        'conditions': [
+          ['target_arch=="x64"', {
+            'android_lib': '<(android_sysroot)/usr/lib64',
+          }, {
+            'android_lib': '<(android_sysroot)/usr/lib',
+          }],
+        ],
         'android_stlport_include': '<(android_stlport)/stlport',
         'android_stlport_libs': '<(android_stlport)/libs',
       }, {
         'variables': {
           'android_sysroot': '<(android_ndk_root)/platforms/android-<(android_target_platform)/arch-<(android_target_arch)',
           'android_stlport': '<(android_ndk_root)/sources/cxx-stl/stlport/',
         },
         'android_include': '<(android_sysroot)/usr/include',
-        'android_lib': '<(android_sysroot)/usr/lib',
+        'conditions': [
+          ['target_arch=="x64"', {
+            'android_lib': '<(android_sysroot)/usr/lib64',
+          }, {
+            'android_lib': '<(android_sysroot)/usr/lib',
+          }],
+        ],
         'android_stlport_include': '<(android_stlport)/stlport',
         'android_stlport_libs': '<(android_stlport)/libs',
       }],
     ],
     # Enable to use the system stlport, otherwise statically
     # link the NDK one?
     'use_system_stlport%': '<(android_webview_build)',
     'android_stlport_library': 'stlport_static',
   },  # variables
   'target_defaults': {
@@ skipping 154 matching lines @@
               '-fPIE',
             ],
             'ldflags': [
               '-pie',
             ],
           }],
         ],
         'target_conditions': [
           ['_type=="executable"', {
             'conditions': [
-              ['target_arch=="arm64"', {
+              ['target_arch=="arm64" or target_arch=="x64"', {
                 'ldflags': [
                   '-Wl,-dynamic-linker,/system/bin/linker64',
                 ],
               }, {
                 'ldflags': [
                   '-Wl,-dynamic-linker,/system/bin/linker',
                 ],
               }]
             ],
             'ldflags': [
@@ skipping 29 matching lines @@
         'ldflags!': [
           '-Wl,-z,noexecstack',
           '-Wl,--gc-sections',
           '-Wl,-O1',
           '-Wl,--as-needed',
         ],
       }],
     ],  # target_conditions
   },  # target_defaults
 }